Semiconductor device and manufacturing method thereof

CROSS-REFERENCE OF THE INVENTION

0001This application claims priority from Japanese Patent Application Nos. 2007-122753 and 2007-143965, the contents of which are incorporated herein by reference in their entireties.

BACKGROUND OF THE INVENTION

00021. Field of the Invention

0003This invention relates to a semiconductor device and its manufacturing method, specifically to a CSP (Chip Size Package) type semiconductor device using a supporter and its manufacturing method.

00042. Description of the Related Art

0005A CSP has received attention in recent years as a new packaging technology. The CSP denotes a small package having about the same outside dimensions as those of a semiconductor die packaged in it. A BGA (Ball Grid Array) type semiconductor device has been known as a kind of CSP. A plurality of ball-shaped terminals made of metallic material such as solder is arrayed on one of surfaces of the BGA type semiconductor device.

0006In order to increase packaging density, reducing a thickness of the semiconductor die is required, which in turn requires reducing a thickness of a semiconductor substrate as well. When the thickness of the semiconductor substrate is reduced, however, carrying the semiconductor substrate becomes impossible since reduced strength of the substrate causes warping and fracturing of the substrate during the manufacturing process. Therefore, it has been practiced that a supporter such as a glass substrate or a protection tape is bonded to one of surfaces of the semiconductor substrate and the semiconductor substrate is reduced in thickness by grinding the other surface of the semiconductor substrate to which the supporter is not bonded.

0007<figref idref="DRAWINGS">FIG. 29</figref> is a cross-sectional view showing an outline of a conventional BGA type semiconductor device with the supporter. A semiconductor integrated circuit <b>101</b> made of elements such as CCD (Charge Coupled Device) type image sensors and CMOS type image sensors is formed in a surface of a semiconductor substrate <b>100</b> made of silicon (Si) or the like. Pad electrodes <b>102</b> that are electrically connected with the semiconductor integrated circuit <b>101</b> are formed on an insulation film <b>103</b> that is formed on the surface of the semiconductor substrate <b>100</b>. The pad electrodes <b>102</b> are covered with a passivation film <b>104</b> made of a silicon nitride film or the like.

0008A supporter <b>105</b> made of a glass substrate or the like is bonded to the surface of the semiconductor substrate <b>100</b> through an adhesive layer <b>106</b> made of epoxy resin or the like. The supporter <b>105</b> is thick enough to firmly support the semiconductor substrate <b>100</b> that is to be reduced in thickness during the manufacturing process and to prevent the supporter <b>105</b> from being warped or fractured. For example, when the thickness of the semiconductor substrate <b>100</b> is to be reduced to about 100 μm, a thickness of the supporter is about 400 μm.

0009An insulation film <b>107</b> made of a silicon oxide film, a silicon nitride film or the like is formed on a side surface and a back surface of the semiconductor substrate <b>100</b>. Wiring layers <b>108</b> each electrically connected with corresponding each of the pad electrodes <b>102</b> are formed on the insulation film <b>107</b> along the side surface and the back surface of the semiconductor substrate <b>100</b>. A protection layer <b>109</b> made of solder resist or the like is formed to cover the insulation film <b>107</b> and the wiring layers <b>108</b>. Openings are formed in the protection film <b>109</b> at predetermined regions on the wiring layers <b>108</b>. There are formed ball-shaped conductive terminals <b>110</b>, each connected with corresponding each of the wiring layers <b>108</b> through corresponding each of the openings, respectively.

0010The semiconductor device described above is manufactured through a process including a process step (so-called dicing process) in which the supporter <b>105</b>, the protection film <b>109</b> and the like are cut with a dicing blade along predetermined dicing lines DL that make borders between individual semiconductor devices.

0011The technology mentioned above is disclosed in Japanese Patent Application Publication No. 2006-93367, for example.

0012Although the semiconductor device described above has the protection film <b>109</b> that covers the wiring layers <b>108</b> connected with the pad electrodes <b>102</b>, poor moisture resistance of the protection film <b>109</b> and the adhesive layer <b>106</b> made of hygroscopic material at a contacting portion with the supporter <b>105</b> or the like causes a problem of reliability that the supporter <b>105</b> comes unstuck from the semiconductor substrate <b>100</b>.

0013The number of dicing lines DL has increased as micro-fabrication has advanced to increase the number of dice per wafer. The conventional manufacturing method in which the dicing is carried out along each of the dicing lines DL at a time causes another problem that the dicing process takes a lot of time. In particular, when a highly rigid material such as a glass substrate is used as the supporter <b>105</b>, difficulty to cut the supporter <b>105</b> makes additional reason to extend time required in the dicing process. In addition, electronic equipment has been required incorporating more functions while reducing its thickness.

0014This invention is directed to offering a semiconductor device with high reliability and a manufacturing method of the semiconductor device that is simplified to enhance productivity, as well as reducing a thickness of the semiconductor device.

SUMMARY OF THE INVENTION

0015This invention is directed to solve the problems addressed above and has following features. This invention offers a semiconductor device having a metal pad formed in a vicinity of a side surface of a semiconductor die and connected with a circuit element in the semiconductor die, an insulation film formed on the side surface and a back surface of the semiconductor die, a metal wiring connected with a back surface of the metal pad and disposed on the insulation film over the side surface and the back surface of the semiconductor die, a protection layer formed to fill a space over the side surface and the back surface of the semiconductor die and a conductive terminal connected with the metal wiring through an opening formed in the protection layer.

0016This invention also offers the semiconductor device wherein the protection layer is composed of a first protection layer and a second protection layer.

0017This invention also offers the semiconductor device further having a supporter that is bonded to the semiconductor die so as to cover a surface of the semiconductor die and the metal pad.

0018This invention also offers a semiconductor device composed of a first semiconductor device having a metal pad formed in a vicinity of a side surface of a semiconductor die and connected with a circuit element in the semiconductor die, an insulation film formed on the side surface and a back surface of the semiconductor die, a metal wiring connected with a back surface of the metal pad and disposed on the insulation film over the side surface and the back surface of the semiconductor die, a protection layer formed to fill a space over the side surface and the back surface of the semiconductor die and a conductive terminal connected with the metal wiring through an opening formed in the protection layer and a second semiconductor device structured in the same way as the first semiconductor device, wherein the second semiconductor device is disposed on the first semiconductor device and the protection layer of the second semiconductor device makes contact with the first semiconductor device.

0019This invention also offers a semiconductor device having a metal pad formed in a vicinity of a side surface of a semiconductor die and connected with a circuit element in the semiconductor die, an insulation film formed on the side surface and a back surface of the semiconductor die, a metal wiring connected with a back surface of the metal pad and disposed on the insulation film over the side surface and the back surface of the semiconductor die, a protection layer formed over the side surface and the back surface of the semiconductor die, a conductive terminal connected with the metal wiring through an opening formed in the protection layer and a conductive film disposed on the protection layer so as to fill a space over the side surface of the semiconductor die.

0020This invention also offers the semiconductor device described above having a supporter that is bonded to the semiconductor die so as to cover a surface of the semiconductor die and the metal pad.

0021This invention also offers a manufacturing method of a semiconductor device including providing a semiconductor substrate on which a metal pad is formed through a first insulation film, bonding a surface of a supporter to a surface of the semiconductor substrate and the metal pad, removing a portion of the semiconductor substrate from its back surface-side to expose the first insulation film, forming a second insulation film all over the back surface of the semiconductor substrate, removing a portion of the first and second insulation films to expose the metal pad, forming a metal wiring connected with a back surface of the metal pad and extending over the back surface of the semiconductor substrate, forming a groove in the surface of the supporter extending partway through a thickness of the supporter, forming a protection layer so as to fill a space over the back surface of the semiconductor substrate and the groove, and forming a conductive terminal electrically connected with the metal wiring through an opening formed in the protection layer.

0022This invention also offers the manufacturing method of the semiconductor device, wherein the forming of the protection layer includes forming a first protection layer and forming a second protection layer on the first protection layer.

0023This invention also offers a manufacturing method of a semiconductor device including providing a semiconductor substrate on which a metal pad is formed through a first insulation film, bonding a surface of a supporter to a surface of the semiconductor substrate and the metal pad, removing a portion of the semiconductor substrate from its back surface-side to expose the first insulation film, forming a second insulation film all over the back surface of the semiconductor substrate, removing a portion of the first and second insulation films to expose the metal pad, forming a metal wiring connected with a back surface of the metal pad and extending over the back surface of the semiconductor substrate, forming a groove in the surface of the supporter extending partway through a thickness of the supporter, forming a first protection layer over the back surface of the semiconductor substrate and the groove, forming a conductive terminal electrically connected with the metal wiring through an opening formed in the first protection layer, and forming a second protection layer on the first protection layer.

0024This invention also offers the manufacturing method of the semiconductor device, wherein the forming of the protection layer includes applying a mold resin.

0025This invention also offers the manufacturing method of the semiconductor device, wherein the forming of the protection layer includes applying a conductive material.

0026This invention also offers the manufacturing method of the semiconductor device, further including reducing the thickness of the supporter.

0027This invention also offers the manufacturing method of the semiconductor device, further including removing the supporter.

0028This invention offers a manufacturing method of a semiconductor device, including bonding a surface of a supporter to a surface of a semiconductor substrate in a wafer form, removing a portion of the semiconductor substrate, forming a groove in the surface of the supporter extending partway through a thickness of the supporter, dividing the supporter to obtain individual semiconductor devices by etching the supporter from its back surface until the groove is exposed.

0029This invention also offers a manufacturing method of a semiconductor device including bonding a tape to a surface of a semiconductor substrate in a wafer form, bonding a surface of a supporter to the tape, removing a portion of the semiconductor substrate, forming a groove in a surface of the tape facing the semiconductor substrate extending partway through a thickness of the tape, forming a protection layer over a side surface and a back surface of the semiconductor substrate having an opening at a location corresponding to the groove, etching the supporter from its back surface until the tape is exposed, dividing the semiconductor substrate and the supporter to obtain individual semiconductor devices by providing a solvent to the exposed tape to unstick the tape from the semiconductor substrate.

0030This invention also offers a manufacturing method of a semiconductor device including bonding a surface of a supporter to a surface of a semiconductor substrate in a wafer form, removing a portion of the semiconductor substrate, forming a groove in the surface of the supporter extending partway through a thickness of the supporter, reducing the thickness of the supporter at a location corresponding to the groove by etching a back surface of the supporter at least at the location corresponding to the groove, and dividing the supporter along the groove to obtain individual semiconductor devices by applying a load to the supporter.

BRIEF DESCRIPTION OF THE DRAWINGS

0031<figref idref="DRAWINGS">FIG. 1</figref> is a cross-sectional view showing a manufacturing method of a semiconductor device according to a first embodiment of this invention.

0032<figref idref="DRAWINGS">FIG. 2</figref> is a cross-sectional view showing the manufacturing method of the semiconductor device according to the first embodiment of this invention.

0033<figref idref="DRAWINGS">FIGS. 3A and 3B</figref> are plan views showing the manufacturing method of the semiconductor device according the first embodiment of this invention.

0034<figref idref="DRAWINGS">FIG. 4</figref> is a cross-sectional view showing the manufacturing method of the semiconductor device according to the first embodiment of this invention.

0035<figref idref="DRAWINGS">FIG. 5</figref> is a cross-sectional view showing the manufacturing method of the semiconductor device according the first embodiment of this invention.

0036<figref idref="DRAWINGS">FIG. 6</figref> is a cross-sectional view showing the manufacturing method of the semiconductor device according the first embodiment of this invention.

0037<figref idref="DRAWINGS">FIG. 7</figref> is a cross-sectional view showing the manufacturing method of the semiconductor device according the first embodiment of this invention.

0038<figref idref="DRAWINGS">FIG. 8</figref> is a cross-sectional view showing the manufacturing method of the semiconductor device according the first embodiment of this invention.

0039<figref idref="DRAWINGS">FIG. 9</figref> is a cross-sectional view showing a manufacturing method of a semiconductor device according to a second embodiment of this invention.

0040<figref idref="DRAWINGS">FIG. 10</figref> is a cross-sectional view showing the manufacturing method of the semiconductor device according to the second embodiment of this invention.

0041<figref idref="DRAWINGS">FIG. 11</figref> is a cross-sectional view showing a manufacturing method of a semiconductor device according to a third embodiment of this invention.

0042<figref idref="DRAWINGS">FIG. 12</figref> is a cross-sectional view showing a manufacturing method of a semiconductor device according to a fourth embodiment of this invention.

0043<figref idref="DRAWINGS">FIG. 13</figref> is a cross-sectional view showing a manufacturing method of a semiconductor device according a fifth embodiment of this invention.

0044<figref idref="DRAWINGS">FIG. 14</figref> is a cross-sectional view showing a manufacturing method of a semiconductor device according a sixth embodiment of this invention.

0045<figref idref="DRAWINGS">FIG. 15</figref> is a cross-sectional view showing a manufacturing method of a semiconductor device according a seventh embodiment of this invention.

0046<figref idref="DRAWINGS">FIG. 16</figref> is a cross-sectional view showing the manufacturing method of the semiconductor device according to the seventh embodiment of this invention.

0047<figref idref="DRAWINGS">FIG. 17</figref> is a cross-sectional view showing the manufacturing method of the semiconductor device according to the seventh embodiment of this invention.

0048<figref idref="DRAWINGS">FIG. 18</figref> is a cross-sectional view showing the manufacturing method of the semiconductor device according to the seventh embodiment of this invention.

0049<figref idref="DRAWINGS">FIG. 19</figref> is a cross-sectional view showing a manufacturing method of a semiconductor device according an eighth embodiment of this invention.

0050<figref idref="DRAWINGS">FIG. 20</figref> is a cross-sectional view showing a manufacturing method of a semiconductor device according a ninth embodiment of this invention.

0051<figref idref="DRAWINGS">FIG. 21</figref> is a cross-sectional view showing the manufacturing method of the semiconductor device according to the ninth embodiment of this invention.

0052<figref idref="DRAWINGS">FIG. 22</figref> is a cross-sectional view showing a stacked layer structure of the semiconductor device according the ninth embodiment of this invention.

0053<figref idref="DRAWINGS">FIG. 23</figref> is a cross-sectional view showing a manufacturing method of a semiconductor device according a tenth embodiment of this invention.

0054<figref idref="DRAWINGS">FIG. 24</figref> is a cross-sectional view showing the manufacturing method of the semiconductor device according to the tenth embodiment of this invention.

0055<figref idref="DRAWINGS">FIG. 25</figref> is a cross-sectional view showing a manufacturing method of a semiconductor device according an eleventh embodiment of this invention.

0056<figref idref="DRAWINGS">FIG. 26</figref> is a cross-sectional view showing the manufacturing method of the semiconductor device according to the eleventh embodiment of this invention.

0057<figref idref="DRAWINGS">FIG. 27</figref> is a cross-sectional view showing the manufacturing method of the semiconductor device according to the eleventh embodiment of this invention.

0058<figref idref="DRAWINGS">FIG. 28</figref> is a cross-sectional view showing the manufacturing method of the semiconductor device according the eleventh embodiment of this invention.

0059<figref idref="DRAWINGS">FIG. 29</figref> is a cross-sectional view showing a conventional semiconductor device.

DETAILED DESCRIPTION OF THE INVENTION

0060A semiconductor device according to a first embodiment of this invention will be explained hereafter referring to the drawings. <figref idref="DRAWINGS">FIG. 1</figref> through <figref idref="DRAWINGS">FIG. 8</figref> are cross-sectional views and plan views of the semiconductor device presented in an order of a manufacturing process. Although the manufacturing process is applied to a semiconductor substrate in wafer form in which a plurality of the semiconductor devices is arrayed in a matrix bordered with predetermined dicing lines DL, the manufacturing process to form one of the semiconductor devices is described hereafter for the simplicity of explanation.

0061First, there is provided a semiconductor substrate <b>2</b> in wafer form made of silicon (Si) or the like, in a surface of which a semiconductor integrated circuit <b>1</b> (a driver circuit or a logic circuit structured by integrating light-receiving elements such as CCD sensors, CMOS sensors or illumination sensors, light-emitting elements, and semiconductor elements such as transistors and interconnections, for example) is formed, as shown in <figref idref="DRAWINGS">FIG. 1</figref>. The semiconductor substrate <b>2</b> is about 300-700 μm thick, for example. An insulation film <b>3</b> (a silicon oxide film formed by thermal oxidation or CVD, for example) of a thickness of 2 μm, for example, is formed on the surface of the semiconductor substrate <b>2</b>.

0062After a metal layer made of aluminum (Al), aluminum alloy or copper (Cu), for example, is formed by sputtering, plating or other film forming method, the metal layer is etched using a resist layer (not shown) as a mask to form pad electrodes <b>4</b> of a thickness of 1 μm, for example, on the insulation film <b>3</b>. The pad electrodes <b>4</b> make electrodes for external connections, which are electrically connected with the semiconductor integrated circuit <b>1</b> or its peripheral components through interconnections (not shown). A power supply voltage, a ground voltage, and various kinds of signals are provided from conductive terminals <b>14</b>, which are to be described, to the semiconductor integrated circuit <b>1</b>, the semiconductor substrate <b>2</b> and the like through the pad electrodes <b>4</b>. There is no restriction on a location where the pad electrode <b>4</b> is placed, and the pad electrode <b>4</b> may be placed above the semiconductor integrated circuit <b>1</b>.

0063Next, a passivation film <b>5</b> (a silicon nitride film formed by CVD, for example) that covers a portion of or all the pad electrode <b>4</b> is formed over the surface of the semiconductor substrate <b>2</b>. The passivation film <b>5</b> shown in <figref idref="DRAWINGS">FIG. 1</figref> is formed to cover a portion of the pad electrode <b>4</b>.

0064Next, a supporter <b>7</b> in wafer form is bonded to the surface of the semiconductor substrate <b>2</b> and the pad electrode <b>4</b> through an adhesive layer <b>6</b> made of epoxy resin, polyimide (photosensitive polyimide, for example), resist, acryl or the like. In this embodiment, a surface of the supporter <b>7</b> facing the semiconductor substrate <b>2</b> is denoted as a top surface while the other surface of the supporter <b>7</b> is denoted as a back surface. When the semiconductor integrated circuit <b>1</b> includes a light-receiving element or a light-emitting element, it is preferable that the adhesive layer <b>6</b> is made of transparent material with a high light transmittance since emitted light from the semiconductor integrated circuit <b>1</b> or incident light to the semiconductor integrated circuit <b>1</b> travels through the adhesive layer <b>6</b>.

0065The supporter <b>7</b> may be a film-shaped protection tape, may be a rigid substrate made of glass, silicon, quartz, ceramics, plastics, metal or the like, or may be made of resin. The supporter <b>7</b> serves to bolster the semiconductor substrate <b>2</b> as well as protecting a surface of elements in the semiconductor substrate <b>2</b>, and its thickness is about 400 μm, for example. When the semiconductor integrated circuit <b>1</b> includes a light-receiving element or a light-emitting element, the supporter <b>7</b> is to be made of transparent or semitransparent material to permit the light to pass through.

0066Next, back grinding using a back surface grinder is applied to a back surface of the semiconductor substrate <b>2</b> so as to reduce the thickness of the semiconductor substrate <b>2</b> to a predetermined thickness (100 μm, for example). The back grinding may be replaced with etching, or with a combination of grinding and etching. The back grinding might not be required, depending on usage or specifications of the final product or an initial thickness of the semiconductor substrate <b>2</b> being provided.

0067Next, predetermined regions of the semiconductor substrate <b>2</b>, which correspond to the pad electrodes <b>4</b>, are selectively etched off from the back surface-side of the semiconductor substrate <b>2</b> to expose portions of the insulation film <b>3</b>, as shown in <figref idref="DRAWINGS">FIG. 2</figref>. The exposed portions are hereafter referred to as openings <b>8</b>. The openings <b>8</b> are formed in a grating pattern turning the semiconductor substrate <b>2</b> in wafer form into divided islands, as shown in <figref idref="DRAWINGS">FIGS. 3A and 3B</figref>.

0068The selective etching of the semiconductor substrate <b>2</b> is hereafter explained referring to <figref idref="DRAWINGS">FIGS. 3A and 3B</figref>. <figref idref="DRAWINGS">FIGS. 3A and 3B</figref> are outline plan views seen from a side of the semiconductor substrate <b>2</b>. <figref idref="DRAWINGS">FIG. 2</figref> corresponds to a cross-sectional view of a section X-X shown in <figref idref="DRAWINGS">FIGS. 3A and 3B</figref>.

0069The semiconductor substrate <b>2</b> may be etched to a shape of a rectangle narrower in width than the supporter <b>7</b>, as shown in <figref idref="DRAWINGS">FIG. 3A</figref>. Or, the semiconductor substrate <b>2</b> may be shaped to have a rugged periphery by etching off portions of the semiconductor substrate <b>2</b> in regions above which the pad electrodes <b>4</b> are formed, as shown in <figref idref="DRAWINGS">FIG. 3B</figref>. The latter structure has larger overlapping area between the semiconductor substrate <b>2</b> and the supporter <b>7</b> and leaves the semiconductor substrate <b>2</b> extended closer to a periphery of the supporter <b>7</b> than the former structure. Therefore, the latter structure is more preferable than the former structure from the standpoint of enhancing the strength of the supporter <b>7</b> to bolster the semiconductor substrate <b>2</b>. Also, warping of the supporter <b>7</b> due to a difference in a coefficient of thermal expansion between the semiconductor substrate <b>2</b> and the supporter <b>7</b> can be prevented with the latter structure, thus cracks in the semiconductor device and separation of the semiconductor substrate <b>2</b> from the supporter <b>7</b> can be prevented. It is also possible to design the semiconductor substrate <b>2</b> in a planar shape that is different from both of the shapes shown in <figref idref="DRAWINGS">FIGS. 3A and 3B</figref>. The rest of the manufacturing process is described for the case in which the semiconductor substrate <b>2</b> is etched to the shape shown in <figref idref="DRAWINGS">FIG. 3A</figref>.

0070The semiconductor substrate <b>2</b> is etched in a way that sidewalls of the semiconductor substrate <b>2</b> are tapered down toward the back surface of the semiconductor substrate <b>2</b> in this embodiment. However, the semiconductor substrate <b>2</b> may also be etched in a way that the sidewalls of the semiconductor substrate <b>2</b> are perpendicular to a principal surface of the supporter <b>7</b> to keep a width of the semiconductor substrate <b>2</b> constant.

0071Next, an insulation film <b>9</b> such as a silicon oxide film or a silicon nitride film is formed by plasma CVD or the like over the side surface and the back surface of the semiconductor substrate <b>2</b> and the opening <b>8</b>. Next, the insulation film <b>3</b> and the insulation film <b>9</b> are selectively etched using a resist layer (not shown) as a mask, as shown in <figref idref="DRAWINGS">FIG. 4</figref>. The insulation film <b>3</b> and the insulation film <b>9</b> formed over a region stretching from a portion of the pad electrode <b>4</b> to the dicing line DL are selectively removed by the etching so that the portion of the pad electrode <b>4</b> is exposed at the bottom of the opening <b>8</b>.

0072Next, a metal layer to make a wiring layer <b>10</b> made of aluminum (Al), copper (Cu) or the like is formed by a film forming method such as sputtering or plating. After that, the metal layer is selectively etched using a resist layer (not shown) as a mask. The etching shapes the metal layer into the wiring layer <b>10</b> that is formed on the side surface and the back surface of the semiconductor substrate <b>2</b> and connected with the pad electrode <b>4</b>, as shown in <figref idref="DRAWINGS">FIG. 5</figref>.

0073Next, an electrode connection layer (not shown, made of stacked layers of nickel and gold, for example) is formed on a predetermined region of the wiring layer <b>10</b>. The electrode connection layer is formed because the wiring layer <b>10</b> made of aluminum or the like is not easily bonded to the conductive terminal <b>14</b> made of solder or the like and because the electrode connection layer prevents a material forming the conductive terminal <b>14</b> from flowing out of the predetermined region of the wiring layer <b>10</b>. The electrode connection layer may be formed after a protection layer <b>13</b> is formed.

0074Next, a groove <b>11</b> reaching partway through the thickness of the supporter <b>7</b> is formed by removing a portion of the passivation film <b>5</b>, the adhesive layer <b>6</b> and the surface of the supporter <b>7</b> with a dicing blade or by dry etching, as shown in <figref idref="DRAWINGS">FIG. 6</figref>. A large number of grooves <b>11</b> are formed in rows and columns in the surface of the supporter <b>7</b> along borders (dicing lines DL) between the individual semiconductor devices. With this, the semiconductor substrate <b>2</b> is divided into semiconductor dice <b>2</b><i>a</i>. The explanation is hereafter given on the semiconductor die <b>2</b><i>a. </i>

0075Although a cross-sectional shape of the groove <b>11</b> is not limited to a V-shape as shown in <figref idref="DRAWINGS">FIG. 6</figref> and may be other shape such as an ellipse or a rectangle as long as a side surface of the adhesive layer <b>6</b> is exposed, it is preferable that the cross-sectional shape of the groove <b>11</b> is the V-shape or a shape that is bent outwardly at its upper portion (a portion close to a surface of the semiconductor die <b>2</b><i>a</i>) from a standpoint of attaining better coverage of the groove <b>11</b> with the protection layer <b>13</b> which is to be described below.

0076Next, there is formed the protection layer <b>13</b> which has openings <b>12</b> at locations corresponding to regions where the conductive terminals <b>14</b> (to be described) are formed, so that the side surface and the back surface of the semiconductor die <b>2</b><i>a </i>and the groove <b>11</b> are covered with the protection layer <b>13</b> that is thick enough to fill whole space over the semiconductor die <b>2</b><i>a </i>and the groove <b>11</b>, as shown in <figref idref="DRAWINGS">FIG. 7</figref>.

0077The protection layer <b>13</b> is formed as described below. First, a mold resin is formed to a thickness that is about 30 μm thicker than the semiconductor die <b>2</b><i>a </i>using screen printing, for example, so that the semiconductor die <b>2</b><i>a </i>is buried in the mold resin that has the openings <b>12</b>.

0078Or, an organic material such as a polyimide resin or a solder resist film may be used as a material to form the protection layer <b>13</b>. Furthermore, an absorptive material that absorbs visible light, infrared ray or the like may be used.

0079The protection layer <b>13</b> may be applied by a dispensing method (a coating method).

0080In this embodiment, as described above, the protection layer <b>13</b> is formed thick enough to completely cover the side surface of the adhesive layer <b>6</b> and to fill the space over the semiconductor die <b>2</b><i>a </i>and the groove <b>11</b>. As a result, the semiconductor device <b>20</b> according to the embodiment of this invention is improved in the moisture resistance compared with the conventional semiconductor device. Even when a solder resist film having poor moisture resistance is used as the protection layer <b>13</b> as in the conventional art, the moisture resistance of the semiconductor device according to the embodiment is maintained because the solder resist film is formed much thicker than in the conventional art.

0081Next, a conductive material (solder, for example) is screen-printed on the electrode connection layer exposed in the opening <b>12</b> in the protection layer <b>13</b>. Ball-shaped conductive terminals <b>14</b> are formed by subsequent thermal treatment to reflow the conductive material, as shown in <figref idref="DRAWINGS">FIG. 8</figref>. The conductive terminals <b>14</b> are not limited to be formed by the method described above, and may be formed by other method such as electrolytic plating or so-called dispensing method in which solder or the like is applied to the predetermined regions using a so-called dispensing method. Each of the pad electrodes <b>4</b> is electrically connected with corresponding each of the conductive terminals <b>14</b> through the wiring layer <b>10</b>, as described above.

0082Although explanation referring to the drawing is omitted, the semiconductor device <b>20</b> may be reduced in thickness by uniformly reducing the thickness of the supporter <b>7</b> from the back surface-side to a predetermined thickness (50 μm, for example).

0083Reducing the thickness is preferably made by mechanical grinding using a back surface grinder or by spin wet etching in which etching is performed using a chemical solution including hydrofluoric acid while the substrate is rotating. Other etching method such as dip etching may be used as long as the entire back surface of the supporter <b>7</b> is etched.

0084Then the CSP type semiconductor device <b>20</b> is completed by dividing the protection layer <b>13</b> and the supporter <b>7</b> using a dicing blade, as shown in <figref idref="DRAWINGS">FIG. 8</figref>. The semiconductor device <b>20</b> is mounted on a printed circuit board through the conductive terminals <b>14</b>.

0085In the semiconductor device <b>20</b> according to the first embodiment, the protection layer <b>13</b> completely covers the entire semiconductor die <b>2</b><i>a </i>and the side surface of the adhesive layer <b>6</b>. As a result, contact between the adhesive layer <b>6</b> and ambient air is suppressed and corrosive material (water, for example) is prevented from infiltrating into the semiconductor integrated circuit <b>1</b> or the adhesive layer <b>6</b>.

0086Next, a semiconductor device and its manufacturing method according to a second embodiment of this invention will be described referring to the drawings. The same structures and manufacturing process steps as in the first embodiment are denoted by the same symbols and explanations on them are omitted.

0087In the semiconductor device <b>20</b> according to the first embodiment, the protection layer <b>13</b> covers all the back surface of the semiconductor substrate <b>2</b>, as shown in <figref idref="DRAWINGS">FIG. 8</figref>. In the semiconductor device <b>30</b> according to the second embodiment, on the other hand, a first protection layer <b>13</b><i>a </i>is formed so as not to cover the back surface of the semiconductor substrate <b>2</b> as shown in <figref idref="DRAWINGS">FIG. 9</figref>, and a second protection layer <b>31</b> having openings is formed over the first protection layer <b>13</b><i>a </i>and the back surface of the semiconductor substrate <b>2</b>, as shown in <figref idref="DRAWINGS">FIG. 10</figref>. The second embodiment features that the conductive terminal <b>14</b> is formed to be connected with the electrode connection layer through the opening formed in the second protection layer <b>31</b>.

0088In the second embodiment, an underfill material with filler, for example, is applied as the first protection layer <b>13</b><i>a </i>by dispensing method. Or, an organic material such as a mold resin, a polyimide resin or a solder resist film may be used as a material to form the first protection layer <b>13</b><i>a</i>. Furthermore, an absorptive material that absorbs visible light, infrared ray or the like may be used. Or, a reflective material that reflects visible light, infrared ray or the like may be used. A solder resist material is used as the second protection layer <b>31</b>.

0089Next, a semiconductor device according to a third embodiment of this invention will be explained referring to <figref idref="DRAWINGS">FIG. 11</figref>. The same structures and manufacturing process steps as in the first or second embodiment are denoted by the same symbols and explanations on them are omitted.

0090The protection layer <b>13</b> in the first embodiment and the first protection layer <b>13</b><i>a </i>in the second embodiment are formed to fill the space over the groove <b>11</b>. In the semiconductor device <b>35</b> according to the third embodiment, on the other hand, a protection layer <b>41</b> having openings is formed to a uniform thickness over the back surface and side surface of the semiconductor substrate <b>2</b> and the groove <b>11</b>. The conductive terminal <b>14</b> is formed to be connected with the electrode connection layer through the opening in the protection layer <b>41</b>. The third embodiment features that a conductive film <b>46</b> is formed to cover the groove <b>11</b> by applying conductive paste (silver paste, for example) using dispensing method. Or, the conductive film <b>46</b> may be formed using screen printing.

0091The semiconductor device <b>35</b> has better moisture resistance than the conventional semiconductor device, since the space over the groove <b>11</b> and the side surface of the semiconductor die <b>2</b><i>a </i>is filled with the conductive film <b>46</b> in the semiconductor device <b>35</b> as described above, after the protection layer <b>41</b> is formed in the same way as the protection layer <b>109</b> is formed in the conventional semiconductor device <b>100</b>. Because the conductive film <b>46</b> is formed, it is made possible to reflect visible light, infrared ray or the like.

0092Quality of a semiconductor device may be degraded when an adhesive layer is formed on the semiconductor integrated circuit <b>1</b>. For example, when the semiconductor integrated circuit <b>1</b> includes a light-receiving element or a light-emitting element, desired quality is not obtained in some cases because incident light to the semiconductor integrated circuit <b>1</b> or emitted light from the semiconductor integrated circuit <b>1</b> is blocked by the adhesive layer. Also, there is a problem that the adhesive layer is deteriorated by light of a specific wavelength such as Blu-Ray and the deteriorated adhesive layer degrades operational quality of the semiconductor device.

0093Therefore, there is no adhesive layer <b>52</b> between the semiconductor integrated circuit <b>1</b> and the supporter <b>7</b> and there is a cavity <b>51</b> formed there instead in a semiconductor device <b>45</b> according to a fourth embodiment of this invention, as shown in <figref idref="DRAWINGS">FIG. 12</figref>. The structure described above offers an effective solution for a semiconductor device (a semiconductor device for receiving Blu-Ray, for example), the operational quality of which would be degraded by presence of the adhesive layer <b>52</b>. Although the structure having the cavity <b>51</b> is described in the fourth embodiment of this invention, the structure having the cavity <b>51</b> may be adopted in the first, second and third embodiments of this invention.

0094When the supporter <b>7</b> is completely removed from the semiconductor device <b>45</b> having the cavity <b>51</b>, there is formed a semiconductor device <b>60</b> according to a fifth embodiment of this invention, which is provided with the adhesive layer <b>52</b> having an opening <b>61</b> above the semiconductor integrated circuit <b>1</b>, as shown in <figref idref="DRAWINGS">FIG. 13</figref>. It should be noted that the supporter <b>7</b> may be removed from the semiconductor devices according to the first, second and third embodiments.

0095Next, a stacked layer type semiconductor device <b>67</b> according to a sixth embodiment of this invention, which is made of vertically stacked semiconductor devices, each provided with the adhesive layer <b>52</b> having an opening <b>61</b> will be described referring to <figref idref="DRAWINGS">FIG. 14</figref>. <figref idref="DRAWINGS">FIG. 14</figref> is a cross-sectional view showing the stacked layer type semiconductor device <b>67</b> in which a first semiconductor device <b>65</b> and a second semiconductor device <b>66</b> are stacked. Each of the first and second semiconductor devices <b>65</b> and <b>66</b> is provided with pad electrodes <b>68</b> exposed to outside in the openings <b>61</b>. The pad electrode <b>68</b> is structured in the same way as the pad electrode <b>4</b> described above, except that the pad electrode <b>68</b> is exposed to outside in the opening <b>61</b>.

0096After each of the first and second semiconductor devices <b>65</b> and <b>66</b> is completed, each of the conductive terminals <b>14</b> of the second semiconductor device <b>66</b> is aligned with corresponding each of the pad electrodes <b>68</b> of the first semiconductor device <b>65</b> and the conductive terminals <b>14</b> and the pad electrodes <b>68</b> are connected with each other by thermo-compression method to complete the stacked layer type semiconductor device <b>67</b>. Although the first and second semiconductor devices <b>65</b> and <b>66</b> of the same kind (the same size) are stacked in the embodiment described above, this invention is not limited to stacking the same kind (the same size) of semiconductor devices and may be applied to stacking different kinds (different sizes) of semiconductor devices as long as each of the pad electrodes <b>68</b> is aligned with corresponding each of the conductive terminals <b>14</b>. Also, it is possible as a matter of course to stack another semiconductor device on the second semiconductor device <b>66</b>.

0097A height of the stacked layer type semiconductor device <b>67</b> can be minimized because the stacked layer type semiconductor device <b>67</b> does not have the supporter <b>7</b>. Because the protection layer <b>13</b> is formed to bury the semiconductor substrate <b>2</b>, in other words, because the space over the side surface and back surface of the semiconductor die <b>2</b><i>a </i>and the groove <b>11</b> is filled with the protection layer <b>13</b>, the first and second semiconductor devices <b>65</b> and <b>66</b> can be brought into close contact with each other so that the stacked layer type semiconductor device <b>67</b> is tolerant of shock and the like. The protection layer <b>13</b> may be composed of the first protection layer <b>13</b><i>a </i>and the second protection layer <b>31</b>.

0098Next, a semiconductor device according to a seventh embodiment will be described referring to <figref idref="DRAWINGS">FIGS. 1 through 6</figref> and <figref idref="DRAWINGS">FIGS. 15 through 18</figref>. Since <figref idref="DRAWINGS">FIGS. 1 through 6</figref> are explained regarding the first embodiment, detailed descriptions on them are omitted. A depth of the groove <b>11</b> shown in <figref idref="DRAWINGS">FIG. 6</figref> is determined considering the thickness of the supporter <b>7</b> after dividing into individual semiconductor devices. For example, when the final thickness of the supporter <b>7</b> is to be approximately 50 μm, the groove <b>11</b> is formed so that its bottom is approximately 70 μm deep from the surface of the supporter <b>7</b>. Even when the groove <b>11</b> is formed with dicing blade, the dicing blade is used only in this process step and is not used in a process step of dividing into individual semiconductor devices, which will be described below. Since a manufacturing method according to the seventh embodiment of this invention includes less number of process steps that require using the dicing blade compared with the manufacturing method that includes the process step to form the groove <b>11</b> using the dicing blade and the process step to obtain the individual semiconductor devices using the dicing blade, total time required by the whole manufacturing process can be reduced with the manufacturing method according to the seventh embodiment.

0099Next, a protection layer <b>21</b> having openings <b>12</b> and <b>18</b> at locations where conductive terminals <b>15</b> are to be formed and the grooves <b>11</b> are formed is formed to a thickness of 10 μm, for example, as shown in <figref idref="DRAWINGS">FIG. 15</figref>. The protection layer <b>21</b> is formed as follows, for example.

0100First, an organic material such as a polyimide resin or a solder resist is applied over the entire surface by coating method and a thermal treatment (pre-bake) is performed.

0101Next, the organic material is subject to exposure and development to form the openings that expose predetermined regions followed by a thermal treatment (post-bake). With this, the protection layer <b>21</b> having the openings <b>12</b> and <b>18</b> at the locations where the conductive terminals <b>15</b> are to be formed and the grooves <b>11</b> are formed is obtained. Although the protection layer <b>21</b> according to the seventh embodiment completely covers the side surface of the adhesive layer <b>6</b>, the protection layer <b>21</b> covers the side surface of the supporter <b>7</b> only at portions close to the semiconductor substrate <b>2</b> and is not formed at least over the dicing lines DL.

0102In other words, the protection layer <b>21</b> extends halfway between the surface of the supporter <b>7</b> and the bottom of the groove <b>11</b>, and is not formed at the bottom of the groove <b>11</b>. By forming the openings <b>18</b> in the protection layer <b>21</b> at the locations corresponding to the grooves <b>11</b>, neighboring semiconductor devices are prevented from remaining connected with each other through the protection layer <b>21</b> after back surface etching which is to be described below, so that individual semiconductor devices are separated appropriately.

0103Next, a conductive material (solder, for example) is screen-printed on the electrode connection layer exposed in the opening <b>12</b> in the protection layer <b>21</b>. Ball-shaped conductive terminals <b>15</b> are formed by subsequent thermal treatment to reflow the conductive material, as shown in <figref idref="DRAWINGS">FIG. 16</figref>. The conductive terminals <b>15</b> are not limited to be formed by the method described above, and may be formed by other method such as electrolytic plating or so-called dispensing method (coating method) in which solder or the like is applied to predetermined regions using a dispenser. Each of the pad electrodes <b>4</b> is electrically connected with corresponding each of the conductive terminals <b>15</b> through the wiring layer <b>10</b> as described above.

0104Next, liquid resist material is applied by spin-coating from the back surface-side of the semiconductor substrate <b>2</b> to form a resist layer <b>16</b> that covers everything including inner walls of the grooves <b>11</b>, the conductive terminals <b>15</b> and the protection layer <b>21</b>. The resist layer <b>16</b> is thick enough to fill the space over the semiconductor die <b>2</b><i>a </i>and the grooves <b>11</b>. Then the resist layer <b>16</b> is hardened by heat treatment. Note that the resist layer <b>16</b> is in contact with the supporter <b>7</b> at the bottom of the groove <b>11</b> since the groove <b>11</b> is filled with the resist layer <b>16</b> through the opening <b>18</b>.

0105Next, a protection material <b>17</b> such as a film-shaped UV (ultraviolet) tape or a glass substrate is bonded to the back surface of the semiconductor die <b>2</b><i>a</i>. The protection material <b>17</b> serves to protect the conductive terminals <b>15</b> as well as bolstering the semiconductor die <b>2</b><i>a </i>in a process step to reduce the thickness of the supporter <b>7</b>, which is to be described below, and in subsequent transportation.

0106Next, the supporter <b>7</b> is thinned to a predetermined thickness (50 μm, for example) by uniformly reducing the thickness from its back surface-side until the groove <b>11</b> and the resist layer <b>16</b> are exposed, as shown in <figref idref="DRAWINGS">FIG. 17</figref>. Reducing the thickness is preferably made by mechanical grinding using a back surface grinder or by spin wet etching in which etching is performed using a chemical solution including hydrofluoric acid while the substrate is rotating. Other etching method such as dip etching may be used as long as the entire back surface of the supporter <b>7</b> is etched.

0107The etching of the supporter <b>7</b> is controlled by a predetermined etching time calculated based on a etch rate, or terminated when exposure of the resist layer <b>16</b> is detected by an optical device or by other means. As described above, the supporter <b>7</b> in wafer form is divided into islands, that is, chip-shaped individual semiconductor devices <b>70</b> are formed all at once.

0108Although the grooves <b>11</b> are exposed on the back surface of the supporter <b>7</b>, it should be noted that the resist layer <b>16</b> remains in the grooves <b>11</b> and the protection material <b>17</b> is bonded to the back surface of the semiconductor die <b>2</b><i>a</i>. Therefore the individual semiconductor devices <b>70</b> are held together. Since the resist layer <b>16</b> and the protection material <b>17</b> serve as barriers, corrosive material such as chemical solution does not infiltrate into the semiconductor die <b>2</b><i>a </i>to degrade the operational characteristics of the semiconductor device <b>70</b>.

0109After the supporter <b>7</b> is thinned from its back surface-side, the semiconductor devices <b>70</b> are transported while they are bonded to the protection material <b>17</b>, with a gap between neighboring semiconductor devices <b>70</b> being tightly filled with the resist layer <b>16</b>. Therefore, it is not likely that the neighboring semiconductor devices <b>70</b> would be brought into contact with each other during transportation and be damaged mechanically.

0110Next, a predetermined solvent is provided from the back surface-side of the supporter <b>7</b> to dissolve the resist layer <b>16</b>. After that, the individual semiconductor devices <b>70</b> separated from the protection material <b>17</b> are picked up. In the case where the protection material <b>17</b> is made of the UV tape, the protection material <b>17</b> is subject to ultraviolet radiation to reduce the adherence so that the semiconductor devices <b>70</b> are easily picked up.

0111It is also possible that another tape is bonded to the back surface of the supporter <b>7</b>, the protection material <b>17</b> is removed, and then solvent is provided from the back surface-side of the semiconductor die <b>2</b><i>a </i>to dissolve the resist layer <b>16</b>.

0112With the process steps described above, the chip size package type semiconductor device <b>70</b> is completed as shown in <figref idref="DRAWINGS">FIG. 18</figref>. The semiconductor device <b>70</b> is mounted on a printed circuit board through the conductive terminals <b>15</b>.

0113In the seventh embodiment of this invention, the individual semiconductor devices are not separated by dicing along each of the dicing lines DL at a time as in the conventional art, but by etching the whole back surface of the supporter <b>7</b>, as described above. Since the semiconductor devices are separated all at once, time required in the dicing process step is significantly reduced to improve productivity.

0114Since the supporter <b>7</b> is thinned and the semiconductor devices are separated all at once, thin semiconductor devices can be manufactured more effectively in the seventh embodiment than in the conventional art. Since the supporter <b>7</b> is thinned after all the components in the semiconductor device such as the wiring layer <b>10</b>, the conductive terminals <b>15</b> and the protection layer <b>14</b> are completed, the forming of each of the components is not affected by the reduction in rigidity of the supporter <b>7</b> due to the reduction in the thickness.

0115Although the grooves <b>11</b> are exposed on the back surface of the supporter <b>7</b> as a result of back surface etching, the resist layer <b>16</b> remains in the grooves <b>11</b> and the protection material <b>17</b> is bonded to the back surface of the semiconductor die <b>2</b><i>a</i>. Thus, corrosive material (fine particles caused in the back surface etching of the supporter <b>7</b> or the chemical solution used in the etching, for example) does not infiltrate into the semiconductor die <b>2</b><i>a </i>to degrade the quality of the semiconductor device <b>70</b>.

0116The protection layer <b>21</b> covers all side surfaces of the adhesive layer <b>6</b> and portions of the side surfaces of the supporter <b>7</b> close to the semiconductor substrate <b>2</b> in the seventh embodiment. As a result, contact between the adhesive layer <b>6</b> and ambient air is suppressed and corrosive material (water, for example) is prevented from infiltrating into the semiconductor integrated circuit <b>1</b> or the adhesive layer <b>6</b>.

0117Next, an eighth embodiment of this invention will be explained referring to the drawings. The same structures and manufacturing process steps as in the seventh embodiment are denoted by the same symbols and explanations on them are omitted.

0118In the seventh embodiment, the back surface of the supporter <b>7</b> is etched off partway through the thickness of the supporter <b>7</b>, as shown in <figref idref="DRAWINGS">FIG. 17</figref>. In the eighth embodiment, on the other hand, the supporter <b>7</b> is completely etched off. The etching of the supporter <b>7</b> is terminated when the supporter <b>7</b> is completely etched off by controlling an etch rate, for example. A semiconductor device <b>75</b> with an uppermost surface made of the adhesive layer <b>6</b> as shown in <figref idref="DRAWINGS">FIG. 19</figref> is obtained through the process described above. In this case, the adhesive layer <b>6</b> serves to protect the surface of the semiconductor die <b>2</b><i>a. </i>

0119Since the semiconductor devices <b>75</b> are separated all at once in the eighth embodiment as in the seventh embodiment, time required in the dicing process step is significantly reduced to improve productivity. Since the supporter <b>7</b> is eliminated, the semiconductor device <b>75</b> according to the eighth embodiment is even thinner than the semiconductor device <b>70</b> according to the seventh embodiment.

0120Next, a ninth embodiment of this invention will be explained referring to the drawings. The same structures and manufacturing process steps as in the seventh or eighth embodiment are denoted by the same symbols and explanations on them are omitted.

0121The adhesive layer <b>6</b> is uniformly formed between the semiconductor substrate <b>2</b> and the supporter <b>7</b> in the seventh and eighth embodiments. In the ninth embodiment, on the other hand, an adhesive layer <b>30</b> is partially formed between the semiconductor substrate <b>2</b> and the supporter <b>7</b> and a cavity <b>31</b> similar to the cavity <b>51</b> in the fourth embodiment is formed between the semiconductor die <b>2</b><i>a </i>and the supporter <b>7</b>, as shown in <figref idref="DRAWINGS">FIG. 20</figref>.

0122The cavity <b>31</b> is an inner space surrounded by the semiconductor die <b>2</b><i>a</i>, the adhesive layer <b>30</b> and the supporter <b>7</b>. It is formed by applying a ring-shaped material of the adhesive layer <b>30</b> on the surface of the semiconductor substrate <b>2</b> followed by bonding it to the supporter <b>7</b>, for example.

0123A semiconductor device having the cavity <b>31</b> is formed by etching the back surface of the supporter <b>7</b> until the grooves <b>11</b> are exposed as described regarding <figref idref="DRAWINGS">FIG. 16</figref> and <figref idref="DRAWINGS">FIG. 17</figref>.

0124As stated in the fourth embodiment, quality of the semiconductor device may be degraded when the adhesive layer is formed on the semiconductor integrated circuit <b>1</b>. For example, when the semiconductor integrated circuit <b>1</b> includes a light-receiving element or a light-emitting element, desired quality is not obtained in some cases because incident light to the semiconductor integrated circuit <b>1</b> or emitted light from the semiconductor integrated circuit <b>1</b> is blocked by the adhesive layer.

0125Also, there is a problem that the adhesive layer is deteriorated by light of a specific wavelength such as Blu-Ray and the deteriorated adhesive layer degrades operational quality of the semiconductor device.

0126Because the cavity <b>31</b> is formed, there is no adhesive layer between the semiconductor integrated circuit <b>1</b> and the supporter <b>7</b> in the semiconductor device according to the ninth embodiment as in the semiconductor device <b>45</b> according to the fourth embodiment. Therefore, the structure described above offers an effective solution for a semiconductor device (a semiconductor device for receiving Blu-Ray, for example), the operational quality of which would be degraded by presence of the adhesive layer.

0127When the supporter <b>7</b> is completely removed from a structure with the cavity <b>31</b> shown in <figref idref="DRAWINGS">FIG. 20</figref> as described in the eighth embodiment, there is formed a semiconductor device <b>80</b> provided with the adhesive layer <b>30</b> having an opening <b>32</b> above the semiconductor integrate circuit <b>1</b>, as shown in <figref idref="DRAWINGS">FIG. 21</figref>. The semiconductor device <b>80</b> is structured similar to the semiconductor device <b>60</b> according to the fifth embodiment shown in <figref idref="DRAWINGS">FIG. 13</figref> which is provided with the adhesive layer <b>52</b> having the opening <b>61</b>.

0128Therefore, as described in the sixth embodiment, it is possible to form a stacked layer type semiconductor device <b>87</b> that is made of vertically stacked semiconductor devices, each provided with the adhesive layer <b>30</b> having the opening <b>32</b>, as shown in <figref idref="DRAWINGS">FIG. 22</figref>. Outline of the stacked layer type semiconductor device is explained referring to <figref idref="DRAWINGS">FIG. 22</figref>, although there may be some duplication in the explanation. <figref idref="DRAWINGS">FIG. 22</figref> is a cross-sectional view showing the stacked layer type semiconductor device <b>87</b> in which a first semiconductor device <b>85</b> and a second semiconductor device <b>86</b> are stacked. Each of the first and second semiconductor devices <b>85</b> and <b>86</b> is provided with pad electrodes <b>38</b> exposed to outside in the opening <b>32</b>. The pad electrode <b>38</b> is structured in the same way as the pad electrode <b>4</b> described above, except that the pad electrode <b>38</b> is exposed to outside in the opening <b>32</b>.

0129After the first and second semiconductor devices <b>85</b> and <b>86</b> are completed, each of the conductive terminals <b>15</b> of the second semiconductor device <b>86</b> is aligned with corresponding each of the pad electrodes <b>38</b> of the first semiconductor device <b>85</b> and the conductive terminals <b>15</b> and the pad electrodes <b>38</b> are connected with each other by thermo-compression method to complete the stacked layer type semiconductor device <b>87</b>. Also, it is possible as a matter of course to stack another semiconductor device on the second semiconductor device <b>86</b>. A height of the stacked layer type semiconductor device <b>87</b> can be minimized because the stacked layer type semiconductor device <b>87</b> does not have the supporter <b>7</b>.

0130Next, a tenth embodiment of this invention will be explained referring to the drawings. The same structures and manufacturing process steps as in the seventh through ninth embodiments are denoted by the same symbols and explanations on them are omitted.

0131The supporter <b>7</b> is thinned by uniformly reducing the thickness from its back surface-side in the seventh through ninth embodiments. In the tenth embodiment, on the other hand, the supporter <b>7</b> is partially etched from its back surface. First, the grooves <b>11</b> and the resist layer <b>16</b> are formed, the protection material <b>17</b> is bonded to the back surface of the semiconductor die <b>2</b><i>a</i>, and a resist layer <b>47</b> having openings <b>40</b> at locations corresponding to the grooves <b>11</b> is formed on the back surface of the supporter <b>7</b>, as shown in <figref idref="DRAWINGS">FIG. 23</figref>.

0132Next, the back surface of the supporter <b>7</b> is partially etched using the resist layer <b>47</b> as a mask to form openings <b>42</b> in the supporter <b>7</b>, as shown in <figref idref="DRAWINGS">FIG. 24</figref>. The openings <b>42</b> are formed in large numbers at locations corresponding to the grooves <b>11</b>, that is, in rows and columns along the borders between the individual semiconductor devices. The etching is carried out until the opening <b>42</b> reaches the groove <b>11</b> to expose the groove <b>11</b> and the resist layer <b>16</b>. As a result, the supporter <b>7</b> in wafer form is separated into islands and chip-shaped individual semiconductor devices <b>43</b> are formed all at once.

0133Wet etching is preferable as a method used in the etching from a standpoint that a large number of substrates are processed all together to reduce time required in the manufacturing process. In this case, the supporter <b>7</b> covered with the resist layer <b>47</b> is placed in a container and submerged in predetermined chemical solution that fills the container. The etching of the back surface of the supporter <b>7</b> may be carried out by dry etching or sand blasting.

0134Although side surfaces of the supporter <b>7</b> stretching from the back surface to the groove <b>11</b> are shown to be tapered by the etching in <figref idref="DRAWINGS">FIG. 24</figref>, it is also possible to make the side surfaces approximately perpendicular to a principal surface of the supporter <b>7</b> when the supporter <b>7</b> is etched by anisotropic etching such as dry etching or by sand blasting.

0135Next, predetermined solvent is provided from the openings <b>42</b> to dissolve the resist layer <b>16</b>. After that, the individual semiconductor devices <b>43</b> separated from the protection material <b>17</b> are picked up.

0136In the tenth embodiment, as described above, the individual semiconductor devices <b>43</b> are not separated by dicing along each of the dicing lines DL at a time as in the conventional art, but by partially etching the back surface of the supporter <b>7</b> using the resist layer <b>47</b> having the openings <b>42</b> along the borders between the individual semiconductor devices. Since the semiconductor devices are separated all at once, time required in the dicing process step is significantly reduced to improve productivity.

0137Next, an eleventh embodiment of this invention will be explained referring to the drawings. The same structures and manufacturing process steps as in the seventh through tenth embodiments are denoted by the same symbols and explanations on them are omitted.

0138A tape <b>50</b> is bonded to the surface of the semiconductor substrate <b>2</b> through the adhesive layer <b>6</b> and the supporter <b>7</b> is bonded to the tape <b>50</b>, as shown in <figref idref="DRAWINGS">FIG. 25</figref>. The tape <b>50</b> is preferably made of a material such as polyimide, which is different from the adhesive layer <b>6</b> or a protection layer <b>55</b> that is to be described below. That is to prevent the adhesive layer <b>6</b> and the protection layer <b>55</b> from being removed when a solvent to reduce viscosity of the tape <b>50</b> is provided later in order to remove the tape <b>50</b>. Next, the openings <b>8</b>, the insulation film <b>9</b> and the wiring layer <b>10</b> and the like are formed in the same process as in the seventh embodiment.

0139Next, a groove <b>53</b> reaching partway through a thickness of the tape <b>50</b> is formed by removing a portion of the passivation film <b>5</b>, the adhesive layer <b>6</b> and the tape <b>50</b> with a dicing blade or by dry etching, as shown in <figref idref="DRAWINGS">FIG. 26</figref>. A large number of grooves <b>53</b> are formed in rows and columns in the surface of the tape <b>50</b> along borders (dicing lines DL) between the individual semiconductor devices.

0140Next, there is formed the protection layer <b>55</b> made of solder resist or the like and having openings <b>12</b> and <b>54</b> at locations corresponding to regions where the conductive terminals <b>15</b> are to be formed and locations corresponding to the grooves <b>53</b>. Although the protection layer <b>55</b> according to the eleventh embodiment completely covers the side surface of the adhesive layer <b>6</b>, the protection layer <b>55</b> covers the side surface of the tape <b>50</b> only at portions close to the semiconductor die <b>2</b><i>a </i>and is not formed at least over the dicing lines DL.

0141In other words, the protection layer <b>55</b> extends halfway between the side surface of the adhesive layer <b>6</b> and a bottom of the groove <b>53</b>, and is not formed at the bottom of the groove <b>53</b>. By forming the openings <b>54</b> at the locations corresponding to the grooves <b>53</b> as described above, neighboring semiconductor devices are prevented from remaining connected with each other through the protection layer <b>55</b> after the tape <b>50</b> is removed, so that the individual semiconductor devices are separated appropriately.

0142Next, the conductive terminal <b>15</b> is formed on the electrode connection layer exposed in each of the openings <b>12</b> in the protection layer <b>55</b>, as shown in <figref idref="DRAWINGS">FIG. 27</figref>. Then, a resist material is applied from the back surface-side of the semiconductor die <b>2</b><i>a </i>to form a resist layer <b>16</b> that covers everything including inner walls of the grooves <b>53</b>, the conductive terminals <b>15</b> and the protection layer <b>55</b>. The resist layer <b>16</b> is in contact with the tape <b>50</b> at the bottom of the groove <b>53</b>. Then, the protection material <b>17</b> is bonded to the back surface of the semiconductor die <b>2</b><i>a. </i>

0143Next, the supporter <b>7</b> is partially etched using the resist layer <b>47</b> to expose the tape <b>50</b>, as described referring to <figref idref="DRAWINGS">FIG. 24</figref>. Then, predetermined solvent is provided to the exposed tape <b>50</b> so that the tape <b>50</b> is removed to separate the semiconductor die <b>2</b><i>a </i>from the supporter <b>7</b>.

0144Next, the resist layer <b>16</b> is removed and individual semiconductor devices <b>56</b> separated from the protection material <b>17</b> are picked up. With the process steps described above, the chip size package type semiconductor device <b>56</b> is completed as shown in <figref idref="DRAWINGS">FIG. 28</figref>.

0145Since the semiconductor devices are separated all at once in the eleventh embodiment as in the seventh through tenth embodiments, time required in the dicing process step is significantly reduced to improve the productivity. Also, since the supporter <b>7</b> is removed, a semiconductor device with reduced thickness is made available.

0146Next, a twelfth embodiment of this invention is described. Explanations on the same structure and manufacturing process steps as in the first through fifth embodiments are omitted or simplified.

0147In the seventh embodiment, the resist layer <b>16</b> covers everything including the inner walls of the grooves <b>11</b>, the conductive terminals <b>15</b> and the protection layer <b>21</b>, as shown in <figref idref="DRAWINGS">FIG. 16</figref>. In the twelfth embodiment, on the other hand, the protection material <b>17</b> is bonded to the back surface of the semiconductor die <b>2</b><i>a </i>without forming the resist layer <b>16</b>. Since a semiconductor device according to the twelfth embodiment is the same as the semiconductor device shown in <figref idref="DRAWINGS">FIG. 16</figref> except that the resist layer <b>16</b> is not formed, a drawing showing the semiconductor device according to the twelfth embodiment is omitted.

0148Then, the back surface of the supporter <b>7</b> is uniformly etched, or a resist layer having openings at locations corresponding to the grooves <b>11</b> is formed on the back surface of the supporter <b>7</b> (Refer to <figref idref="DRAWINGS">FIG. 23</figref>.) and the supporter <b>7</b> is partially etched using the resist layer as a mask.

0149The etching is carried out until the grooves <b>11</b> are exposed so that the supporter <b>7</b> in wafer form is separated into islands and chip-shaped individual semiconductor devices are formed all at once in the seventh and tenth embodiments. In the twelfth embodiment, on the other hand, the etching is stopped before the grooves <b>11</b> are exposed. That is, the thickness of the supporter <b>7</b> is extremely reduced at the locations corresponding to the grooves <b>11</b>. The thickness of the supporter <b>7</b> at the locations is 50-100 μm, for example.

0150Because the etching is not carried out until the grooves <b>11</b> are exposed, even though the resist layer <b>16</b> is not formed, the supporter <b>7</b> serves as a barrier to prevent corrosive material (fine particles caused in the back surface etching of the supporter <b>7</b> or chemical solution used in the etching, for example) from infiltrating into the semiconductor substrate <b>2</b> to degrade the quality of the semiconductor device.

0151Next, physical or mechanical load, or pressure, is applied to the locations where the supporter <b>7</b> is thinned so that the supporter <b>7</b> is separated along the grooves <b>11</b>. To be more specific, the supporter <b>7</b> is separated by applying predetermined pressure from the back surface-side of the supporter <b>7</b> toward the surface-side along the grooves <b>11</b> using a human hand or a predetermined tool.

0152The supporter <b>7</b> in wafer form is divided into islands, that is, chip-shaped individual semiconductor devices are formed, as described above.

0153It is possible, as described above, to form the individual semiconductor devices through the two process steps (the process step to etch the back surface of the supporter <b>7</b> and the process step to apply the pressure to the locations corresponding to the grooves <b>11</b>. The manufacturing method described above has a merit that the corrosive material is prevented from infiltrating into the semiconductor die <b>2</b><i>a </i>without forming the resist layer <b>16</b>. Also, since using a dicing blade is not necessary, time required by the dicing process can be saved. In addition, the productivity can be enhanced, because the individual semiconductor devices can be obtained all at once by applying the pressure successively or simultaneously to all the locations corresponding to the grooves <b>11</b> on the back surface of the supporter <b>7</b>.

0154It is apparent that this invention is not limited to the embodiments described above and may be modified within the scope of the invention. For example, although the BGA type semiconductor devices having ball-shaped conductive terminals are described in the embodiments, this invention may be applied to an LGA (Land Grid Array) type semiconductor device and other CSP (Chip Size Package) type semiconductor devices.

0155Also, although the conductive terminals are formed on the back surface of the semiconductor substrate in the embodiments described above, the conductive terminals may be disposed on a side surface of the semiconductor substrate.

0156Although the protection layer <b>14</b> or <b>54</b> is formed in the seventh or twelfth embodiment, respectively, this invention may be applied to a semiconductor device in which no protection layer is formed, and may be widely applied as a manufacturing method to effectively obtain chip-shaped individual semiconductor devices. In this case, a metallic material (copper, for example) that is highly resistant to corrosive materials such as water is preferably used as the wiring layer <b>10</b>.

0157This invention can offer the semiconductor devices with improved moisture resistance compared with the conventional structure, because the protection layer is formed to fill the space over the semiconductor die in the semiconductor devices according to the embodiments of this invention. Also, according to the embodiments of this invention, time required in dicing process can be significantly reduced to improve the productivity, because the individual semiconductor devices can be obtained all at once without dicing along each of the dicing lines at a time. In addition, the semiconductor devices can be reduced in thickness, because the manufacturing method according to the embodiments of this invention includes thinning the supporter or removing the supporter.